President’s Message: 2008 CDR Users Conference:
Allow
me to pose a hypothetical construct. You were driving your
car at night on the way home after a long day. Traffic was
light in the 30mph zone and you waited in the left turn lane
for the light to change. You saw a break in the traffic and
accelerated. Suddenly you were broadsided by an oncoming
car. The police find you at fault for an unsafe turn. Your
only defense is that you thought you had time and the other
guy must have been speeding. The other driver, a teenager
driving his dad’s new Impala, admits he was in a hurry to
get home, but says he wasn’t speeding when you pulled out in
front of him. An accident reconstruction puts his speed
between 28 and 33 mph at impact. Are you out of luck? The
answer may lie in the CDR.
Last
month I attended the 2008 CDR Users Conference in Houston,
Texas. The 2007 conference had about 150 attendees, this
conference had 270 from all over the US and Canada. CDR
stands for Crash Data Retrieval, (or Recorder) which
narrowly is applied to any vehicle with an air bag, and more
broadly is applied to vehicles with electronic recording
capability for their various powertrain control systems
(such as delivery trucks and 18 wheelers). EDR (Event Data
Recorder) is another commonly used term.
Here
is a brief overview. Auto manufacturers (Original Equipment
Manufacturers or OEMs) installed air bags to make vehicle
crashes more survivable-to save lives. One of the first
things that the engineers knew they had to do was monitor
air bag effectiveness. Did the devices either fail to
deploy when they should, or did they deploy unnecessarily?
To track this, they installed system recorders that
documented speeds and impact forces. General Motors (GM)
was the pioneer. Early devices provided a fairly elementary
snapshot of what happened a few milliseconds before, during,
and after a crash that involved an air bag deployment. As
technology improved, the recording devices and sensors
became more sophisticated. Some Fords provide 6 minutes of
pre-crash data.
GM
looked at the various diagnostic electronic devices that
they bought from their suppliers, and realized that they
could more effectively contract with a single vendor to
provide the diagnostic equipment, instead of multiple
competing vendors or doing it in-house. They then signed an
exclusive license agreement with a company called Vetronix
to develop the software and hardware required to extract the
data from the EDRs. A few years later, Ford made a similar
decision and also signed up with Vetronix.
By
now the word was out, and new stakeholders became involved
in the CDR industry. Police began to recognize that CDR
information could be used as additional evidence in
prosecuting vehicular crimes. Accident Reconstructionists
also sought to be able to use this information for their
clients. What used to be the sole province of the OEMs now
was opened up to a much larger community as Accident
Reconstructionists, insurance companies and police
departments began to buy the Vetronix equipment.
For
more than a decade, only GM and Ford vehicles could be
interrogated by the Vetronix equipment. All other OEMs
considered their information proprietary. Safety is a
primary sales feature and most OEMs were very reluctant to
possibly share any information with their competition.
Aside from GM and Ford, a subpoena or court order were
generally required to force a manufacturer to share CDR
information. The federal government has now stepped in and
dictated that all OEMs make their information public by 2012
(by NHTSA Part 563).
A new
issue was raised, relating to privacy, “Is the driver
testifying against himself - or who owns the information?”
The answer depends on the jurisdiction. I once listened to
an hour presentation just on the legal differences between
states. Privacy advocates have had limited success in their
assertion that the CDR information is protected from police
searches by the self-incrimination rule. Some jurisdictions
say that the driver of the car at the time of the crash owns
the information. Some states extend computer privacy
legislation to cover CDRs. Some states bar CDR information
from transferring to the new owner of a salvaged vehicle.
Most states consider the owner of the car to be the owner of
the CDR information. This will probably hit the Supreme
Court in the next decade-until then, the rules vary. German
law, by the way, is extremely privacy oriented (think
Porsche/BMW/autobahn).
So
what kind of information is available? There is no
standard list –every model is different, depending on year
manufactured and options ordered but here are 5 data
elements commonly recorded from 5 seconds before the crash
through a second after:
-
Vehicle speed
-
Throttle opening percentage
-
Engine rpm
-
Seat belt buckled or not
-
Brake light circuit activated or not
The
federal 2012 rule requires 18 distinct data elements. The
‘08 Impala currently provides 118 elements, and most cars
number in the tens of distinct data elements, so it’s not
like the OEMs are dragging their feet.
A
couple years ago, Bosch bought out Vetronix’s CDR business,
and they are beginning to re-label it as they release new
equipment. At the conference, they addressed various
technical topics related to CDR equipment and development.
There currently are under 10,000 active users of the Bosch/Vetronix
CDR equipment. The equipment connects the vehicle (or CDR)
to the user’s laptop computer and runs the Bosch software to
translate the raw data into useful information. Currently
GEI has 22 different cables and adapters to fit the various
different models. The software is constantly updating as
OEMs release additional options and models, as well as
modifying earlier settings. Users are trained and certified
by Bosch approved courses. Downloading a CDR is NOT
plug and play-it is a very technical process. You
have to know what you are doing and be current on the latest
technical procedural changes and software updates.
Vehicles are becoming increasingly sophisticated, depending
upon the manufacturer and the options. Side air curtains and
roll over protection change the dynamics from a simple
frontal deceleration (on the x axis) to 3 dimensional
controls (adding the y and z axis of the car). Roll Over
Sensors record lateral and vertical acceleration, roll rate
history, active faults and some models even record steering
angles that tells you where the wheels were pointed when it
crashed (did they try to drive around the obstacle?).
The
big news in the industry is that Chrysler has now also
contracted with Bosch for CDR downloads, starting with the
2004 model year for selected model SUVs, trucks and
crossover vehicles. Compliance with Part 563 is not an easy
task as, while NHTSA attempted to standardize reporting
requirements, each manufacturer has different design
criteria and uses different EEPROMs, resistors, capacitors,
diodes, accelerometers, switches, and air bags from a
multitude of vendors. As an example, between GM, Ford, and
Chrysler some record data each second, some each 2/10ths of
a second, and some each 1/10th of a second.
Let
us return to your hypothetical crash. If your CDR
technician downloads the EDR, what will he find? Perhaps
the Impala’s speed was a steady 32 mph with seatbelts
buckled and brake activation at 1 second before impact. On
the other hand, perhaps at 10 seconds before impact the
throttle was wide open at 100% and at 5 seconds before
impact the teenager’s speed was 92 mph. If the later was
the case, even though he slowed down to the speed limit at
the time of impact, he clearly was the cause of the
accident, and you are off the hook. CDR downloads can be a
very useful tool to use “When You Need To Know What Really
Happened”.